Thanks for the quick reply! And the pricing would completely be worth it if it solves what I need. I'm on NVIDIA, if that helps.
I'm definitely not good enough with shaders to write something that would give that gentler lighting effect I'm after. Shaders are hard as hell, so kudos for what you've written.
Is it possible to toggle both "plane" lighting and put a normal map edge lighting effect on top of it, like you demonstrate in the docs you sent? I know that often times these different draw methods are organized as separate functions in libraries like this.